991 resultados para Uncertain demand


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The paper presents a demand side response scheme,which assists electricity consumers to proactively control own demands in such a way to deliberately avert congestion periods on the electrical network. The scheme allows shifting loads from peak to low demand periods in an attempt to flattening the national electricity requirement. The scheme can be concurrently used to accommodate the utilization of renewable energy sources,that might be available at user’s premises. In addition the scheme allows a full-capacity utilization of the available electrical infrastructure by organizing a wide-use of electric vehicles. The scheme is applicable in the Eastern and Southern States of Australia managed by the Australian Energy Market Operator. The results indicate the potential of the scheme to achieve energy savings and release capacity to accommodate renewable energy and electrical vehicle technologies.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The problem of decision making in an uncertain environment arises in many diverse contexts: deciding whether to keep a hard drive spinning in a net-book; choosing which advertisement to post to a Web site visitor; choosing how many newspapers to order so as to maximize profits; or choosing a route to recommend to a driver given limited and possibly out-of-date information about traffic conditions. All are sequential decision problems, since earlier decisions affect subsequent performance; all require adaptive approaches, since they involve significant uncertainty. The key issue in effectively solving problems like these is known as the exploration/exploitation trade-off: If I am at a cross-roads, when should I go in the most advantageous direction among those that I have already explored, and when should I strike out in a new direction, in the hopes I will discover something better?

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper, we describe, in detail, a design method that assures that the designed product satisfies a set of prescribed demands while, at the same time, providing a concise representation of the design that facilitates communication in multidisciplinary design teams. This Demand Compliant Design (DeCoDe) method was in itself designed to comply with a set of demands. The demands on the method were determined by an analysis of some of the most widely used design methods and from the needs arising in the practice of design for quality. We show several modes of use of the DeCoDe method and illustrate with examples.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We consider a robust filtering problem for uncertain discrete-time, homogeneous, first-order, finite-state hidden Markov models (HMMs). The class of uncertain HMMs considered is described by a conditional relative entropy constraint on measures perturbed from a nominal regular conditional probability distribution given the previous posterior state distribution and the latest measurement. Under this class of perturbations, a robust infinite horizon filtering problem is first formulated as a constrained optimization problem before being transformed via variational results into an unconstrained optimization problem; the latter can be elegantly solved using a risk-sensitive information-state based filtering.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Emergency Health Services (EHS), encompassing hospital-based Emergency Departments (ED) and pre-hospital ambulance services, are a significant and high profile component of Australia’s health care system and congestion of these, evidenced by physical overcrowding and prolonged waiting times, is causing considerable community and professional concern. This concern relates not only to Australia’s capacity to manage daily health emergencies but also the ability to respond to major incidents and disasters. EHS congestion is a result of the combined effects of increased demand for emergency care, increased complexity of acute health care, and blocked access to ongoing care (e.g. inpatient beds). Despite this conceptual understanding there is a lack of robust evidence to explain the factors driving increased demand, or how demand contributes to congestion, and therefore public policy responses have relied upon limited or unsound information. The Emergency Health Services Queensland (EHSQ) research program proposes to determine the factors influencing the growing demand for emergency health care and to establish options for alternative service provision that may safely meet patient’s needs. The EHSQ study is funded by the Australian Research Council (ARC) through its Linkage Program and is supported financially by the Queensland Ambulance Service (QAS). This monograph is part of a suite of publications based on the research findings that examines the existing literature, and current operational context. Literature was sourced using standard search approaches and a range of databases as well as a selection of articles cited in the reviewed literature. Public sources including the Australian Institute of Health and Welfare (AIHW), the Council of Ambulance Authorities (CAA) Annual Reports, Australian Bureau of Statistics (ABS) and Department of Health and Ageing (DoHA) were examined for trend data across Australia.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article augments Resource Dependence Theory with Real Options reasoning in order to explain time bounds specification in strategic alliances. Whereas prior work has found about a 50/50 split between alliances that are time bound and those that are open-ended, their substantive differences and antecedents are ill understood. To address this, we suggest that the two alliance modes present different real options trade-offs in adaptation to environmental uncertainty: ceteris paribus, time-bound alliances are likely to provide abandonment options over open-ended alliances, but require additional investments to extend the alliance when this turns out to be desirable after formation. Open-ended alliances are likely to provide growth options over open-ended alliances, but they demand additional effort to abandon the alliance if post-formation circumstances so desire. Therefore, we expect time bounds specification to be a function of environmental uncertainty: organizations in more uncertain environments will be relatively more likely to place time bounds on their strategic alliances. Longitudinal archival and survey data collected amongst 39 industry clusters provides empirical support for our claims, which contribute to the recent renaissance of resource dependence theory by specifying the conditions under which organizations choose different time windows in strategic partnering.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This chapter argues that evolutionary economics should be founded upon complex systems theory rather than neo-Darwinian analogies concerning natural selection, which focus on supply side considerations and competition amongst firms and technologies. It suggests that conceptions such as production and consumption functions should be replaced by network representations, in which the preferences or, more correctly, the aspirations of consumers are fundamental and, as such, the primary drivers of economic growth. Technological innovation is viewed as a process that is intermediate between these aspirational networks, and the organizational networks in which goods and services are produced. Consumer knowledge becomes at least as important as producer knowledge in determining how economic value is generated. It becomes clear that the stability afforded by connective systems of rules is essential for economic flexibility to exist, but that too many rules result in inert and structurally unstable states. In contrast, too few rules result in a more stable state, but at a low level of ordered complexity. Economic evolution from this perspective is explored using random and scale free network representations of complex systems.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective: Hospital EDs are a significant and high-profile component of Australia’s health-care system, which in recent years have experienced considerable crowding. This crowding is caused by the combination of increasing demand, throughput and output factors. The aim of the present article is to clarify trends in the use of public ED services across Australia with a view to providing an evidence basis for future policy analysis and discussion. Methods: The data for the present article have been extracted, compiled and analysed from publicly available sources for a 10 year period between 2000–2001 and 2009–2010. Results: Demand for public ED care increased by 37% over the decade, an average annual increase of 1.8% in the utilization rate per 1000 persons. There were significant differences in utilization rates and in trends in growth among states and territories that do not easily relate to general population trends alone. Conclusions: This growth in demand exceeds general population growth, and the variability between states both in utilization rates and overall trends defies immediate explanation. The growth in demand for ED services is a partial contributor to the crowding being experienced in EDs across Australia. There is a need for more detailed study, including qualitative analysis of patient motivations in order to identify the factors driving this growth in demand.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: Emergency departments (EDs) are critical to the management of acute illness and injury, and the provision of health system access. However, EDs have become increasingly congested due to increased demand, increased complexity of care and blocked access to ongoing care (access block). Congestion has clinical and organisational implications. This paper aims to describe the factors that appear to infl uence demand for ED services, and their interrelationships as the basis for further research into the role of private hospital EDs. DATA SOURCES: Multiple databases (PubMed, ProQuest, Academic Search Elite and Science Direct) and relevant journals were searched using terms related to EDs and emergency health needs. Literature pertaining to emergency department utilisation worldwide was identified, and articles selected for further examination on the basis of their relevance and significance to ED demand. RESULTS: Factors influencing ED demand can be categorized into those describing the health needs of the patients, those predisposing a patient to seeking help, and those relating to policy factors such as provision of services and insurance status. This paper describes the factors influencing ED presentations, and proposes a novel conceptual map of their interrelationship. CONCLUSION: This review has explored the factors contributing to the growing demand for ED care, the influence these factors have on ED demand, and their interrelationships depicted in the conceptual model.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Depleting fossil fuel resources and increased accumulation of greenhouse gas emissions are increasingly making electrical vehicles (EV) attractive option for the transportation sector. However uncontrolled random charging and discharging of EVs may aggravate the problems of an already stressed system during the peak demand and cause voltage problems during low demand. This paper develops a demand side response scheme for properly integrating EVs in the Electrical Network. The scheme enacted upon information on electricity market conditions regularly released by the Australian Energy Market Operator (AEMO) on the internet. The scheme adopts Internet relays and solid state switches to cycle charging and discharging of EVs. Due to the pending time-of-use and real-price programs, financial benefits will represent driving incentives to consumers to implement the scheme. A wide-scale dissemination of the scheme is expected to mitigate excessive peaks on the electrical network with all associated technical, economic and social benefits.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Successful identification and exploitation of opportunities has been an area of interest to many entrepreneurship researchers. Since Shane and Venkataraman’s seminal work (e.g. Shane and Venkataraman, 2000; Shane, 2000), several scholars have theorised on how firms identify, nurture and develop opportunities. The majority of this literature has been devoted to understanding how entrepreneurs search for new applications of their technological base or discover opportunities based on prior knowledge (Zahra, 2008; Sarasvathy et al., 2003). In particular, knowledge about potential customer needs and problems that may present opportunities is vital (Webb et al., 2010). Whereas the role of prior knowledge of customer problems (Shane, 2003; Shepherd and DeTienne, 2005) and positioning oneself in a so-called knowledge corridor (Fiet, 1996) has been researched, the role of opportunity characteristics and their interaction with customer-related mechanisms that facilitate and hinder opportunity identification has received scant attention.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In approaching this Special Issue on Foresight, Innovation and Entrepreneurship (FI&E) we considered that globalisation and rapid modernisation were increasingly creating the need for social reflexivity. We thought that in respect to the production and diffusion of innovations, both social and technical, that the landscape for new enterprise was characterised by widening change horizons and deeper ethical concerns. As a consequence of the greater demand for innovation to achieve economic prosperity, it was conceived that 'unforesightful' innovation may have irreparable affects on social and ecological systems and uncertain implications for our futures. Therefore, we considered a new intellectual alliance between FI&E was potentially a matter of human survival. New approaches to thinking about how and what we innovate, the choices we face for new enterprise creation and the influence of infrastructure for generating entrepreneurship, we considered, would need to emerge if we are to positively impact human and planetary sustainability in the 21st century. Hence this special issue was designed to bring together cross-disciplinary research aimed at exploring the synergies between foresight, innovation and entrepreneurship and the way in which these connections may be taking place in both the practical and theoretical sense.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In Queensland, at least 93 bodies exist to represent the interests of, and provide other services for, their farmer members, and their industries. The bodies vary greatly in focus, roles and activities, priorities, resources, size, and affiliations with other bodies. Results from a survey of 68 producer representative bodies (PRBs), and other data and information are used to examine the demand for, and supply of, farmer representational and other services in Queensland. The main results were: 1. member demand for services varies considerably between PRBs and is influenced by numerous factors; 2. members and non-members of one PRB vary significantly in the importance attached to some services; 3. the types of activities undertaken by PRBs varies between those for emerging and established industries; and 4. PRBs with paid staff/officers undertake more activities than others. The paper concludes that PRBs must continue to evolve and adapt their operations and structures to take account of changes in member and industry needs, external environments, cost pressures, resource availability, and sources of funding/assistance.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Hybrid system representations have been exploited in a number of challenging modelling situations, including situations where the original nonlinear dynamics are too complex (or too imprecisely known) to be directly filtered. Unfortunately, the question of how to best design suitable hybrid system models has not yet been fully addressed, particularly in the situations involving model uncertainty. This paper proposes a novel joint state-measurement relative entropy rate based approach for design of hybrid system filters in the presence of (parameterised) model uncertainty. We also present a design approach suitable for suboptimal hybrid system filters. The benefits of our proposed approaches are illustrated through design examples and simulation studies.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The application before the court in Millerview Constructions Pty Ltd v Palmer Plumbing Pty Ltd [2008] QSC 005 raised a significant question regarding the appropriate construction of s 459G of the Corporations Act 2001 (Cth) (the Act). The decision emphasises the importance of ensuring that any application to set aside a statutory demand must be served in a timely way on the creditor at the creditor’s address for service as stated in the statutory demand, or in strict compliance with another manner authorised by the Act.